From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shlomo Pongartz <shlomop@mellanox.com>
Subject: GRO aggregation
Date: Tue, 11 Sep 2012 16:45:07 +0300
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Hi,

I=92m checking GRO aggregation with kernel 3.6.0-rc1+ using Intel ixgbe=
=20
driver.
The mtu is 1500 and GRO is on and so are SG and RX checksum.
I ran iperf with default setting and monitor the receiver with tcpdump.
The tcpdump shows that the maximal aggregation is 32120 which is 21 * 1=
500.
In the transmitter side tcpdump shows that TSO works better (~64K).
I did a capture without GRO enabled to see if there was a difference=20
between any flag
of any two consecutive packets that forced flushing but didn't find=20
anything.
Is the GRO aggregation can be tuned.



Shlomo Pongratz